Flat-sheet oxygenator

FIGURE 23.4 Schematic diagram of flat sheet BOs. Q and Co refer to the inlet and outlet oxygen concentrations in the liquid phase. 

Gu YJ, Boonstra PW, Graaff R, Rijnsburger AA, Mungroop H, and van Oeveren W. Pressure drop, shear stress, and activation of leukocytes during cardiopulmonary bypass A comparison between hollow fibre and flat sheet membrane oxygenators. Artif. Organs 2000 24(1) 43 8. 

Vibratory mechanism was one more interesting technique for reducing fouling negative effect. Vibrations can be apphed to flat sheet membrane modules, but many researchers tested the technique on performance of hollow fibers for different separation processes [3, 136]. One example of construction is shown in Fig. 9.10 [136] to assess the effect of axial membrane vibrations on mass transfer in a hollow fiber oxygenator. 

In 1956 Clowes and coworkers described an oxygenator using flat sheets of membrane to separate the blood and gas (Figure 2). Clowes examined Teflon, ethyl cellulose, polyethylene, cello-... 

Low-density polyethylene and polypropylene in the form of flat-sheet and hollow-fiber membranes are used in plasmapheresis and as oxygenators in the heart-lung machine. Other materials commonly used in plasmapheresis are cellulose acetate, polycarbonate, and polysulfone [129]. 

Gas permeation experiments were carried out for carbon dioxide, oxygen and nitrogen. The method used to measure the gas permeability was the constant pressure or variable volume method. For the measurements a home-made system was used [32]. It comprised a two-compartment flat sheet permeability cell. The feed stream circulates in the bottom compartment tangentially to the composite films and permeates through them to be collected in the top compartment where a flowmeter is connected. Due to the asymmetry of the composites the permeation experiments were carried out both for the top and bottom surfaces of the composite films facing the feed stream. 

Figure 20 J SchematizatioD of the experimental setup of the integrated photocatalysis-MD process. (1) Magnetic stirrer, (2) feed (artificial turhid water) tank, (3) and (4) circulation pumps, (5) hoUow-liher module or flat-sheet membrane, (6) thermostated photoreactor, (7) pressure regulation valve, and (8) oxygen cylinder.

Sharing of three of the four oxygen atoms in each tetrahedron with neighboring tetrahedra, to form flat sheets Phyllosilicate Phyllos, sheet... 

As mentioned in Section 14.3, biofilm is heterogeneous and contains dead and living microorganisms. The images obtained by CLSM showed that dead bacteria accumulated in the sublayer in thickened biofilm on a flat sheet hydrophilic polypropylene membrane, used in MBR [61]. In other MBR-based studies, CLSM was used to assess the fouled membrane at different dissolved oxygen... 

A method to modify dense PPO films throughout the thickness of the separating layer was developed by Kramer et al. They carried out chemical oxidation on flat sheet dense membranes of PPO. The reaction was done by exposing PPO dense membranes to a mixture of ozone and oxygen. The concentration of ozone used was in the range of 5-5.6 percent in a carrier of oxygen. Ozonation was believed to significantly increase the gas selectivity of... 

Dense ceramic membranes allow oxygen or hydrogen permeation in a dissociated or ionized form other than the conventional molecular diffusion, and thus exhibit extremely high selectivity (up to 100%). They can be incorporated into membrane reactors for a variety of oxidation and dehydrogenation reactions where the membrane functions as either a product extractor or a reactant distributor. Three configurations, that is, disc/flat-sheet, tubular and hollow fibre membranes have been applied in membrane reactors. They exhibit respective advantages/disadvantages in terms of the ease and cost of fabrication, the effective membrane area/volume ratio, and... 

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