Membranes can be divided into the following types according to the shape of membrane:

Sheet membrane: membrane with the shape of flat sheet or paper.

Tube membrane: membrane with the shape of tube, with a self-supporting layer.

Spiral-wound module: membrane with the shape of coil, with a supporting layer.

Hollow fiber membrane: membrane with hollow fibrous shape, with self-supporting function.

Feature and superiority of hollow fiber:

Low running pressure with energy efficiency. It can be cleaned by backwashing (other kinds of membrane is difficult to complete backwashing and cleaning for them is difficult).

The largest filling density in cell space, and large surface area with less land occupation.

Gas cleaning is allow to membrane cleaning.

Easy to complete integrity inspection and easy make-up (easier than other kinds of membrane for leakage inspection and make-up).