Membrane Structures

Anything higher than the maximum would destroy the elements of the membrane. If a higher temperature is needed, we recommend Filmtec’s “Heat Sanitizable” membrane. JIUWU ceramic membrane element must be treated with great care during transportation, to avoid impact, knock and press and should be kept protected from dampness and extreme temperature. The types of ceramic membrane element are composed of the code and the Arabic numerals by the follow rules. JIUWU ceramic membrane element is an ideal choice for high value-added products and demanding selective separations from solid-liquid fluid streams. The compact multi-channel geometry and high permeability are optimized for bulk processing applications.

“O” ring seals 6, 6a, 6b, 6c, 6d, 6e and 6f are shown as solid dark rectangles at the principle points where the membrane element or its various nozzles are connected to ports of the membrane element 1, the pressure vessel 2, its end plates 2a and 2b. At the center of the RFP membrane element 1 is a porous core tube 3 around which the membrane sheets 15 and spacers are spirally wound. 1, the porous core tube 3 contains a tube plug 4 at the product end of membrane element 1 to prevent mixing of feed and permeate at the product end in the porous plate 5 which serves as a conduit for the product leaving the pressure vessel 2 through a permeate nozzle 11. Both lateral edges of the membrane element 1 are potted in a low viscosity adhesive 7a and 7b which seals the membrane and spacer ends and bonds the membranes and spacers to the optional end cups 9a and 9b. In place of end cups 9a and 9b the membrane element 1 can be optionally sealed in a glue “cup” of the same dimensions.

5 and 5a are views of the non-recessed portion of the membrane element 1 of FIG. 5 the solid spiralling lines represent the membrane sheets 15 and the spaces between represent the feed-concentrate and permeate flow channels with spacers and adhesive 7a omitted. Openings contained in feed end cup 9a allow the concentrate to pass out of the circumferential chamber 8 into an open space about a feed nozzle 12 and thence exit from the pressure vessel 2 through a concentrate nozzle 13.

These stiffness factors are ignored for axisymmetric membrane elements. There are no hourglass stiffness factors or scale factors for the nondefault enhanced hourglass control formulation. For axisymmetric membrane elements the positive normal is defined by a 90� counterclockwise rotation from the direction going from node 1 to node 2.

Membrane Structures

The pressure is positive in the direction of the positive element normal. Plate elements have three degree of freedoms per node out of which two dofs are in-plane rotations and one dof corresponds to the out of plane translation. Plate is a particular case of shells having no initial curvature. If a structrual element has width/thickness ration greater than 10 then it can be treated as shell which can withstand only membrane loads, and hence, there will be no variation in the out-of-plane stresses. Since Plate can have out of plane forces, Plate is not a membrane element for most of the cases.

One downside to using hollow fiber membranes is that they have proven to have almost no effect on COD removal, resulting in subsequent RO plugging from organic pollutants. Secondly, these traditional filtration methods have been unable to meet improvements made to environmental protection requirements that set the standard for COD levels in RO permeate water, which has dropped from an allowance of 500 to 200 mg/L. Dixon Valve manufactures these membrane elements from high-quality polypropylene materials. Construction occurs in a cleanroom environment and is free of surfactants, resins, binders, and adhesives. Plate elements are 3 or 4 node 2D planar elements that can be oriented anywhere in 3D space. They are typically used to model structures comprised of shells such as pressure vessels, automobile bodies, ship hulls, and aircraft fuselages.

A single modulus of elasticity and Poisson’s ratio will be the requested material properties. In geometrically nonlinear analyses the cross-section thickness changes as a function of the membrane strain with a user-defined “effective section Poisson’s ratio,” . where is the Cauchy stress, is the virtual rate of deformation , and V is the current volume of the membrane.

The cantilevered beam shown in Figure 4 is meshed by five irregular quadrilateral membrane elements depicted in Figure 6. Two cases of loading are considered, Load 1 is the force couple acting at the two corners on the free end, and Load 2 is two equal transverse forces acting at the two corners. The numerical results given by QCQ4-1 and QCQ4-2 are tabulated in Table 4 together with the results given by a number of other popular quadrilateral membrane elements for comparison.

You can usually specify either all tetrahedra, all bricks, or a mixture of both with some automatic mesh generators. This is the most common, and frequently the only element type supported by automatic mesh generators. Bricks work quite well for any “blocky” structures which are typical of machined, cast, or forged fabricated parts.

The substitute for the production of high purity water and guarantees a low cost of the water treatment system. Dow Filmtec™ LC LE-4040 provides high quality permeate even with low quality inlet water and low pressure. The vertical displacement at the middle point of the free edge and the maximum stress at the middle of the bottom edge given by QCQ4-1 and QCQ4-2 and other quadrilateral membrane elements are tabulated in Table 6. The reference displacement and stress for this problem are taken from . Most of researchers only examined the accuracy of the computed deflection at the bottom corner at the free end of the cantilevered beam illustrated in Figure 6.

Although the concentration of membrane components in the aqueous phase is low , there is an exchange of molecules between the lipid and aqueous phases. The operating flow rate should be achieved gradually over a period of seconds. Polyimide film can be used at a higher temperature (35 ° C) than cellulose acetate (30 ° C); destroyed by chlorine, but is resistant to most bacteria; while some bacteria may actually destroy the cellulose acetate. Finally, the polyamides may be used in a much wider range of pH (4 – 11) than cellulose acetate (4 – 7.5).

INDUSTRIAL APPLICABILITY As described above, the present invention has high industrial applicability since it has a feature enabling the reuse of the membrane element and the like. As an example of the microporous filtration membrane 1, a Yumicron membrane manufactured by Yuasa Corporation, which has a number of micro pores with average pore size of 0.4 μm, can be used. The microporous filtration member 1 having such average pore size is called as a microfiltration membrane according to the definition of JIS K 3802. The aforesaid plate 2 as used is made of an acrylonitrile-butadiene-styrene copolymer resin. Providing each microporous filtration membrane 1 on the plate 2 in tension is achieved by joining the peripheral part of the plate 2 to the microporous filtration membrane without fusing the nonwoven fabric acting as the substrate 11. 2, when pressed by a linear-shaped hot plate disposed along the positioning line 21, the plate 2 is softened to have a recess, into which the microporous filtration membrane 1 is drawn, as represented by arrows.