(559c) Design and Optimization of Sea Salt Particles Filter for Naval Fuel Cell Using Microfibrous Materials (MFM)

Presence of sea salt particles (SSP) in the ocean atmosphere could cause severe degradation in fuel cell performance on Naval Ships. Therefore, the removal of these particles from the air stream fed to the cathode side of the fuel cell is essential. Current approach is using coalescors and inertial separators to remove the particles. But these devices are only effective for particles larger than 8 microns in size. To remove much smaller particles in a more efficient manner, we focused on the design and optimization of a new type of salt particles filter. The filter media in this case is a composite material known as Microfibrous Materials (MFM), which was manufactured by us in facility and has shown great applicability in removing particulate matters. However, MFM has substantially higher flow resistance than traditional filtration media due to decreased fiber diameter and tighter packing density. Thus, MFM is limited to be applied as media for air filters. Multi-Element Structured Arrays (MESA’s) that developed by our group represent a new approach that can increase the filtration area and reduce the pressure drop across the filter by integrating several filters into a single unit. In this study, both single filter and MESA’s were tested on an 8’’x 8’’ test rig for the filtration performance, including particle removal efficiency and pressure drop across the system. After comparing the results, MESA’s could reduce the initial pressure drop by almost 70% and provide higher removal efficiency. The effects of varying fiber type, fiber diameter, media thickness, MESA’s counts were also experimentally investigated. Additionally, we entrapped activated carbon particles (<200 microns) with different diameter sizes and quantities into Microfibrous Materials (MFM); then filtration performances were evaluated and compared. By modifying previous semi-empirical model and changing different parameters, optimization of filter design to get the highest particle removal efficiency with lowest energy consumption could be achieved.