Module configuration

The intrinsic rejection and maximum obtainable water flux of different membranes can be easily evaluated in a stirred batch system. A typical batch unit (42) is shown in Figure 5. A continuous system is needed for full-scale system design and to determine the effects of hydrodynamic variables and fouling in different module configurations. A typical laboratory/pilot-scale continuous unit using computer control and on-line data acquisition is shown in Figure 6. 

Three-layer membrane tube (in module configuration, 10 tubes per module, heat exchanger type). 

Porous supported y-AljOj tube (in module configuration), membrane thickness 4-10 pm, mean pore diameter 0.01 im. Feed enters the reactor at shell side, permeate at tube side. 

Hollosep High Rejection Type is characterized by Cellulose Tri Acetate (CTA) hollow fiber with dense membrane structure and high salt rejection, and also by the module configuration favorable for uniform flow of feed water through hollow fiber layers (5 ). These features suggest that Hollosep may be operated under the conditions of higher recovery ratio compared to conventional conditions. 

Figure 7.2 Simple two-stage membrane module configuration (Adapted from Ref. [28]).

With the aim to avoid or to reduce the membrane fouling, which causes the membrane flux decline, another type of membrane module configuration of PMR,... 

The major market for membrane bioreactors is represented by wastewater treatment with the use of submerged modules configuration. These are considered among the best available technologies by the European Directives on Environment. Membrane bioreactors are also applied in food, red and white biotechnology. In these cases, the external loop configuration is used. 

Figures 23-28 show the process of producing basic circuit elements of vertically stacked circuits. The use of the three lithographic masking techniques mentioned results in very low loss transitions between optical circuits in different vertical stacks. These techniques can also be used to fabricate the low loss electro-optic modulator configuration shown in Figs. 29 and 30.

First commercial hollow-fiber membrane module developed by DuPont. This module configuration further increased the packing density of membrane modules. 

There are four basic forms for RO membrane modules Plate and frame, tubular, spiral wound, and hollow fine fiber. These four configurations are summarized in Table 4.3 and discussed below. Additionally, some manufacturers have developed other module configurations that are briefly discussed in Chapter 4.3.5. 

Table 4.3 Brief comparison of four basic RO membrane module configurations.22...

Some manufacturers have developed unique module configurations that rely on novel methods of introducing turbulence into the feed... 

Microfiltration and UF membranes are available in tubular, spiral wound, and hollow fiber membrane module configurations. Tubular and spiral MF and UF modules are similar to RO tubular and spiral wound membrane modules described in Chapters 4.3.2 and 4.3.3. However, while the thickest feed spacer in a spiral RO module is 34-mil, UF and MF modules nominally have up to a 45-mil spacer due to the relatively high concentration of suspended solids these membranes are called upon to treat (TriSep Corporation offers a special 65-mil spacer for dairy applications). 

Table 16.3 Summarizes the advantages and limitations of tubular, spiral wound and hollow fiber module configurations.

Table 16.3 Advantages and limitation of various module configurations for microfiltration and ultrafiltration membranes.

Transfer of software modules, configuration, graphics, data, and other software objects needs to be managed and controlled formally when building the validation and live environment. Control is also required over the development environment to avoid rework and inefficient software development. 

Bodzek, M. and K. Konieczny (1998). Comparison of various membrane types and module configurations in the treatment of natural water by means of low-pressure membrane methods. Separation Purification Technol, 14, 1-3, 69-78. 

Comparison of process-related characteristics of various module configurations of organic polymer membranes... 

Figure 3 Possible module configurations for IMRs. (a) Flat membranes (b) tubular membranes.

The standard module configurations are presented below. With the development of new membrane materials for various applications (as discussed in Section 4.3), new configurations for optimum gas separation may be expected on the market in the future. 

An assessment of the literature over a wide range of operating conditions and feeds indicates that flux enhancement for tubular membrane filtration can be affected by module configuration and operation conditions such as feed concentration, liquid velocity, bubble size, and TMP. The trends have been summarized by Cui et al. [77], as follows ... 

Chang S and Fane AG, Filtration of biomass with lab-scale submerged hollow fiber membrane module Effect of operational conditions and module configuration, J. Chem. Technol. Biotechnol. 2002 77 1030-2212. 

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