Hollow fiber membrane modules and processes

Hollow fiber membrane modules and processes

Hollow fiber membranes are tubular membranes with an outer diameter of less than 1000 μm.

Figure 10-20 Basic structure of tubular hollow fiber membrane module

When designing the component structure and process, you need to start from the following main aspects

①The symmetry of the membrane For a membrane with a symmetrical structure, in principle, both internal pressure and external pressure can be used, but the internal pressure process or the external pressure process should be determined according to the strength of the membrane and the pressure on both sides of the membrane during operation; When the strength is low and the pressure difference between the two sides of the membrane is large, the outer pressure shell process should be used [the shell process can withstand pressure up to 1000psi (1psi=6894.

②The internal pressure process of the U-shaped module is a full filtration process, and there is no concentrated material export or raw material liquid circulation, which is very easy to form membrane pollution and is not suitable for the separation of fluid mixtures with high suspended solids content.

③Using the combination of component structure and process to reduce membrane pollution and realize self-cleaning, that is, cross-flow or circulation of raw material fluids, and increase the flow rate of the membrane surface to control the adsorption and concentration polarization of pollutants on the membrane surface.

The fluid, especially the hydrodynamic distribution of the raw material fluid in the module is an important factor that determines the effect and efficiency of many membrane separation processes (membrane contact process).

Figure 10-21 Tubular hollow fiber membrane module structure using material distribution tube (collection)

The hollow fiber membrane modules of the above-mentioned structures all pack the membrane bundle into a tubular container.

In the module, the hollow fiber membranes are arranged in parallel into a sheet shape, and the two ends are fixed in the water collection pipe with glue seals

Figure 10-22 Curtain membrane module structure

Figure 10-23 Modular membrane module

Related Links: Rolled Membrane Modules and Processes