Sediments reinjection

We have shown that fractions collected from broad particle distributions can be reinjected into the sedimentation FFF device for a second run (18). The emerging peaks are relatively narrow, reflecting their small particle size range. Quite obviously, a reinjected fraction run in a carrier of a different density will emerge at a different volume because of the effect of Ap on retention parameter X (see Equation 3). The shift in retention volume (see next section) can be used to calculate the density of the particulate material exactly as outlined for monodisperse populations. 

Similarly, collected fractions can be reinjected into the sedimentation FFF system operated with a different carrier density. The degree to which the retention volume for any particle type is shifted by this operation will depend upon the density of the particle. In theory, the shape of the fractogram following fraction reinjection will yield a density distribution curve for the fraction. 

Hart 1984), or the reinjection of sediments (Weaver et al. 1987) or old anomalous Pb material from the mantle lithosphere (Richardson et al. 1982 Hawkesworth et al. 1986) into the convecting mantle. 

From the beginning of the project, the average injection rate of polymer solution was kept dose to 420 m3/day. The cumulative volume of solution injected has been nearly equal to the cumulative volume of oil and water produced from wells located in the enhanced oil recovery zone (fig. 4 and 5). The polymer was diluted in treated field water. Produced formation water was separated from the oil and the sediments (shale particles) under anaerobic conditions and formaldehyde was added at an active concentration of 300 ppm to kill the bacteria. The water was then distributed to the polymer-mixing stations (fig. 6). The polymer was supplied in a water-oil emulsion form containing 30% active polymer dissolved in water. Because the continuous phase is oil, an inverter was added to the water before mixing. The polymer solution was then filtered through 10 micron screens before reinjection into the formation. 

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