We first began be experimenting with 30ppi polyurethane foam. Our experimental setup consisted of a column consisting of 10 layers of 2.54cm foam. We then ran 5, 20, and 50NTU water with a residual alum concentration of 1.5 mg/L through the filter for 24 hours using an approach velocity of 4 mm/s.
Figure 1: 30ppi foam, 50 NTU influent
Figure 2: 30ppi foam, 50 NTU influent
Figure 3: 30ppi foam, 20 NTU influent
Figure 4: 30ppi foam, 20 NTU influent
Figure 5: 30ppi foam, 5 NTU influent
Figure 6: 30ppi foam, 5 NTU influent
We also want to ensure that we would get a consistent and predictable performance from 30ppi foam. In order to verify this, we ran the experiment with a 50 NTU influent 2 additional times and compared the results from the 3 trials.
Figure 7: 30ppi foam, 50 NTU influent experiment comparison
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