Depth Filtration Experiments
In previous experimental trials, it appeared that more particles were captured in the top layer than in either of the bottom foam layers. Over time, a film on the top surface of the foam would accumulate, thus leading to more particles being trapped on the surface. This observation is indicative of foam filtration potentially acting as a straining process, which is a function of surface area, rather than as a filtering process, which is a function of filter depth. It is important to understand which parameter guides the filtration performance, as it will ultimately determine which parameter is optimized in the filtration unit design. Therefore, a series of experiments were run in order to determine whether the foam filtration acts as a function of depth, or rather, as a function of surface area.