Abstract: The invention concerns a method for capturing very fine particles present in a fluid flux in liquid, gaseous or supercritical state and a device therefor. The method is characterized in that it comprises steps which consist in: causing said flux to pass through a filtering element (13); stopping the emission of said flux; countercurrent clearing of the filtering material (31) with a carbon dioxide flow under pressure, so as to drive the particles deposited on the filtering material (31); countercurrent expanding of the flux, so as to trap the particles within a solid carbon dioxide snow-type mixture formed during its expansion.

Abstract: A chromatographic simulated moving bed separation process is most generally characterized by a recycling pump which successively adopts the flow rate characteristics of 4 or 5 zones of the process. The invention describes the method by which a conventional simulated moving bed separator process can be adapted to a simulated moving bed process in which the recycling pump is operated at an optimal constant flow rate. In order to achieve this, throughout the cycle all the introduction and extraction circuits are shifted using independent means, such that the eluted volume at the outlet to each zone remains substantially constant, zone by zone, between two successive shifts throughout the cycle.

Abstract: In a simulated mobile bed separation process, perturbations are corrected in the compositions of an extract (EA) or raffinate (RB) due to the dead volume introduced by at least one recycling pump (P) or compressor for a liquid, supercritical or gaseous mixture in a closed circuit of column sections. The volume of the section immediately upstream of the dead volume is reduced by an appropriate value when said dead volume is located downstream of this section and upstream of the extraction streams of said section, or the volume of the section immediately downstream of the dead volume is reduced by an appropriate value when the dead volume is located downstream of the injection streams into said section and upstream of this section.The invention is applicable to the separation of isomers of aromatic hydrocarbons containing 8 carbon atoms.

Abstract: Perturbations are corrected in the compositions of an extract (EA) or raffinate (RB) due to the dead volume introduced by at least one recycling pump (P) for a liquid, supercritical or gaseous mixture in a closed circuit of column sections, or due to a degradation in their separating power each time an injection or extraction stream passes from a position anterior to a position posterior to each of the dead volumes in the circuit or each section whose separation power has been degraded. Firstly, the connection period for said stream to the circuit is increased by an appropriate value, and then when the stream passes from the posterior position to the dead volume, or connection to the degraded section, to the following position, the connection period is reduced so that the period regains the value which would have been applied if each of the dead volumes had been ignored or the degradation in the separation powers had been ignored.