Centrifugal separation measurements

CENTRIFUGAL SEPARATION. Theoretical as well as experimental studies have been made on the separation of powder in a cyclone by Nishihara, Kori, and Yoshi-zumi (1G). The inner distributions of velocity are measured, and a method of calculating the separable size of powder is presented. 

Laboratory Extractors. Pilot-Scale Testing, and Scale-Up. Several laboratory units arc useful in analysis, process control, and process studies. The AKUFVE contactor incorporates a separate mixer and centrifugal separator. It is an efficient instrument for rapid and accurate measurement of partition coefficients, as well as for obtaining reaction kinetic data. Miniature mixer-settler assemblies set up as continuous, bench-scale, multistage, countercurrent, liquid-liquid contactors are particularly useful Tor the preliminary laboratory work associated with flow-sheet development and optimization because these give a known number of theoretical stages. 

The pressure extraction system (see Fig. 5.1) is operated as follows. The quantity of petroleum from each oil well (produced with the natural layer pressure) is serially measured using an automatic group measurement unit. Then, the petroleum from various oil wells in the field is transported to the local separation station. The quantity of the petroleum from the oil wells is measured after the preliminary gas separation with the centrifugal separator. After that, the petroleum and gas are directed to a local separation unit, where gas is separated from the petroleum by the first stage separator at the pressure 4—5 bar and then directed to the gas processing station. Petroleum with layer water and solved gases will be pumped to the central processing station, where the second step of separation... 

One of the simplest experiments is to establish how much polymer is adsorbed onto the surface. This is known as the adsorbed amount and is determined from the adsorption isotherm (see Fig. 1). The adsorption isotherm relates the amount of polymer adsorbed at an interface to its equilibrium solution concentration. Determination of the adsorbed amount almost always involves measurement of the polymer concentration in solution before and after equilibration with a dispersion of known surface area. This usually requires separation of the dispersion particles from the supernatant by centrifugation. Separation of the bound and free polymer by dialysis can also be used but it is difficult to determine the amount of polymer that may be adsorbed onto the dialysis membrane. As these techniques require a knowledge of the amount of polymer removed from solution, they are known as depletion methods. 

In the laboratory, the goal of most measurement campaigns is to further ones understanding of the basic phenomena that govern the performance of cyclone and related centrifugal separation apparatus. Such things as ... 

When deciding how best to measure the pressure drop over centrifugal separation equipment, we first have to decide what we mean by the term pressme drop . 

Nienow AW, Bartlett R The measurement and prediction of particle-slip velocities in agitated vessels. In Proceedings of the 1st European conference on mixing centrifugal separation, Cambridge, UK, Bl, 1974, pp 1-15. 

The water and sediment contents of crude oils is measured according to the standard methods NF M 07-020, ASTM D 96 and D 1796, which determine the volume of water and sediments separated from the crude by centrifuging in the presence of a solvent (toluene) and of a demulsifylng agent Table 8.13 gives the bottom sediment and water content of a few crude oils. 

The analysis demonstrates the elegant use of a very specific type of column packing. As a result, there is no sample preparation, so after the serum has been filtered or centrifuged, which is a precautionary measure to protect the apparatus, 10 p.1 of serum is injected directly on to the column. The separation obtained is shown in figure 13. The stationary phase, as described by Supelco, was a silica based material with a polymeric surface containing dispersive areas surrounded by a polar network. Small molecules can penetrate the polar network and interact with the dispersive areas and be retained, whereas the larger molecules, such as proteins, cannot reach the interactive surface and are thus rapidly eluted from the column. The chemical nature of the material is not clear, but it can be assumed that the dispersive surface where interaction with the small molecules can take place probably contains hydrocarbon chains like a reversed phase. 

---