Hollow fiber module

A hollow fiber fluid separation module comprising:

• an inlet for an inlet feed flow, an outlet for an exit flow;
• an access port for a permeate flow, a discharge port for the permeate flow, a module axis and a plurality of hollow fibers;
• each of the fibers extending from the inlet to the outlet and comprising an interior communicating with the inlet at one end of each hollow fiber and with the outlet at the other end of each hollow fiber, with the hollow fibers being wound in multiple layers to form a hollow cylindrical coil;
• each layer being defined on its inner side by an imaginary cylinder and having a number of hollow fibers helically wound on the cylinder with a helix angle .alpha.;
• the fibers being in a clearance relationship with each other and equally spaced on the cylinder, with one layer differing from a neighbouring layer by the fact that all the fibers of the one layer are inclined at the wind angle plus .alpha. whereas all the fibers of the neighbouring layer are at the wind angle minus .alpha.;
• and
• each fiber being wrapped 360° at least once around the associated cylinder and being laid down during winding with a tensile strain high enough for the fiber to be frictionally held in the best possible manner to the crosswise disposed fibers lying underneath and low enough for the hollow fibers not to have their inner cross section noticeably restricted even though they are deformed at the intersections and for all of the hollow fibers to be applied with the same tensile strain.