Film contactors

The sweetening process utilizes a caustic solution, catalyst, and aii. Mercaptans are converted to disulfides in a mixing vessel or fiber film contactor. The reactions take place according to the following equations... 

The mixture of caustic and disulfides is transferred to a settler. From the settler, the treated gasoline flows to a coalescer, sand filter, or wash water tower, before going to storage. The caustic solution is recirculated to the mixing vessel/fiber film contactor. 

FIBER-FILM contactor. Developed by Merichem Company, Houston, TX, and used in 11 installations in 1991. 

Fig. 4.11. Laminar-film contactors (a) wetted-wall and (b) wetted-sphere...

In the laminar-film contactor shown in Fig. 4.116, the supporting surface has the form of a sphere held in place by a wire<3>. This arrangement has the advantage that, in the regions where the liquid runs on to the sphere, and where it leaves the sphere, the surface areas exposed to the gas are relatively small so that, even if the hydrodynamics of the liquid flow in these regions is not ideal, the effect on the rate of absorption of the gas will be small. As in the case of the cylindrical tube, the contact time for each element of liquid as it flows around the sphere can be calculated from the liquid flowrate, although the mathematics of the analytical treatment is somewhat more complicated than in the case of the tube. 

Zhivkova, S., Dimitrov, K., Kyuchoukov, G. and Boyadzhiev, L. (2004) Separation of zinc and iron by pertraction in rotating film contactor with Kelex 100 as a carrier. Separation and Purification Technology,... 

Dimitrov, K., Rollet, V., Saboni, A. and Alexandrova, S. (2008) Recovery of nickel from sulphate media by batch pertraction in a rotating film contactor using Cyanex 302 as a carrier. Chemical Engineering and Processing, 47, 1562. 

Both phases in a continuous form packed columns thin-film contactors wetted-wall columns contactors with flat surface laminar jet absorber disc (sphere) columns... 

AQUAFTNING A process for extracting water and other nonsulfur-containing contaminants from petroleum fractions by the use of a proprietary bundle of hollow fibers called a FIBER-FILM contactor. Developed by Merichem Company, Houston, TX, and used in 11 installations in 1991. 

North and Wells (N7) described the design and operation of a rotary-film contactor for the solvent extraction of metals directly from leached ore slurries. It consists of an enclosed rotating assembly of closely spaced disks centrally mounted on a common horizontal shaft. The transfer of the metal to the solvent layer is effected by the rotating disks where a film of slurry is formed on contact with the leached ore at the bottom of the vessel. This contactor gave excellent uranium recovery from sulfuric... 

FIGURE 13.9 Scheme of a creeping film contactor F, R—inlet and outlet of the feed and receiving solutions, respectively E—FLM organic solution. (From Boyadzhiev, L. and Lazarova, Z., Chem. Eng. Sci., 42, 1131, 1987. With permission.)... 

Dimitrov K, Alexandrova S, Saboni A, Debray E, and Boyadzhiev L. Recovery of zinc from chloride media by batch pertraction in a rotating film contactor. J Mem Sci, 2002 207(1) 119-127. 

Suspended-Fiber Contactor The Merichem Fiber-Film contactor is used in petroleum refining operations to wash hydrocarbon streams with caustic or other treating solutions [Suarez, U.S. Patent... 

FIG. 15-58 Merichem Fiber-Film contactor. [Courtesy ofMerichem Chemieals and Refinery Services, LLC.)... 

Film theory says that the gas-liquid interface is separated from the bulk gas and liquid phases by a gas film on one side and a liquid film on the other. While Fig. 1 shows this specifically for bubble or droplet systems, it is easily extended to liquid film contactors as well. Resistance in both films decreases the concentration of species diffusing across the gas-liquid interface irrespective of whether that diffusion is from gas to liquid (as depicted in Fig. 1) or from liquid to gas. 

Figure 5.7 Scheme of a rotating film contactor (1) body, (2) stage wall, (3) feed/strip-ping solution separating walls, (4) rotating disks, and (5) common shaft. From Ref. [12] with permission. 

Further advantages are the small holdup and the short contact time. Klemm et al. [99] applied microstructured film contactors for the evaporation of hydrogen peroxide that was then used for the partial oxidation of propene to methyloxirane. 

Kashid, M. N., Harshe, Y. M., Agar, D. W. (2007a). Liquid-liquid slug flow in a capillary An alternative to suspended drop or film contactors. Industrial and Engineering Chemistry Research, 46, 8420-8430. 

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