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Figure 1: Sloping Column Lime feeder //
With the new apparatus, as shown in figure-2 below, four sets of trials were carried out and evaluated.
The apparatus was first tested with tap water in trial 1 and trial 2 and then with distilled water in trial 3 and 4.
It had been observed that after a few hours into any experimental run, the lime, instead of remaining in suspension as soluble particles, formed a single mass and became insoluble. It was hypothesized (by the previous research team) that this happened because some or all of the lime got converted into calcium carbonate(which is insoluble)if tap water was used since the water at Cornell is alkaline in nature. This should not be a problem in Honduras because the raw water to be treated is not as alkaline. However, under laboratory conditions, in order to get a true estimate of the lime feeder's efficiency (in dissolving lime for a longer period and thereby lasting for a longer time) distilled water was used because it has no alkalinity. In the pictures below, the ANC Control team can be seen carrying the distilled water tank on to the platform where the experiment is to be set up.
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