| Abstract: |
Reverse osmosis (RO) desalination has become the benchmark for the shipboard production of freshwater since its introduction into the Navy in the late 1980s. The 12,000 gallons per day (gal/d) “Navy Standard” RO (NSRO) desalination system was designed when nearly all Navy ship operations were in open ocean and continues to be the design basis for desalination on new ship construction.
The NSRO system includes a series of single-use, disposable string-wound cartridge filters (20 micron [µm] and 3 µm) for removal of entrained suspended solids in the incoming seawater that could foul or plug the RO membranes. In the relatively clean “blue water” of the open oceans, this filtration configuration is very effective with the cartridge filters typically operating for more than 1,000 hours before requiring replacement and RO elements routinely lasting more than 3 years before needing cleaning or replacement. |