‘Feed spacer’ in filtration by reverse osmosis and ultrafiltration
Extruded polypropylene mesh is specifically used as a “feed spacer” in filtration by reverse osmosis (RO) and ultrafiltration. It is the process of purifying or desalinating water by filtering it under high pressure through multiple layers of membranes, which are held at bay by PP extrusion mesh. The PP mesh or “feed spacer” separates two membrane layers. The bi-planar structure of the spacer mesh allows the supply (feed) to reach the membranes efficiently. In an RO filter, the PP feed spacer and membranes are wrapped multiple times around a perforated tube in which the filtered fluid collects, then is discharged.
Features PP mesh ideal as a feed spacer
The bi-planar structure of extruded polypropylene mesh makes it a perfect feed spacer. Polypropylene extruded mesh offers the rigidity to provide equal spacing and support across the entire surface of the membrane. This maintains the required flow with minimal pressure loss. The thinness of our mesh minimizes membrane damage.
Thicknesses of PP mesh
Our polypropylene feed spacer meshes are produced in various thicknesses ranging from 21 mil (0.5 mm) to 80 mil (2 mm).
Co-extruded mesh and woven mesh
For mesh thicknesses less than 0.5 mm, Top Zeven offers woven mesh. However, weaving does not offer high stability like extrusion does. The solution:“co-extruded mesh. Co-extruded polyester mesh is woven from co-extruded threads (PET threads with a soft surface that allows the threads to fuse together using heat after weaving). This makes the mesh stable and makes it possible to weave with thin threads in an open structure. Result: a very thin and open mesh that is still very stable.
Looking for a specific solution?
Tell us, we are happy to think with you. Send your request to mesh [at] topzeven [dot] com or call us at 023 5319051.