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The team used the same procedure described on materials and methods. The lime was added as dry powder. For the up-flow velocity of 3.6 mm/sec, it was calculated that 20g of lime were required for the effluent to be saturated for 12 hours. The amount of lime was calculated as explained in Experiment 1., proportions were kept.
Results
Figure 1. shows effluent pH over time. The green line represents the 2.5cm diameter tube settler, and the 5cm diameter tube settler is represented by yellow and orange lines. We can see that none of the runs were anywhere close to reaching the goal of twelve hours with a saturated effluent. Both tap water and distilled water runs with the 5cm diameter tube settler failed within an hour and a half, while the run with the 2.5 cm diameter tube settler never produced any saturated effluent. There is certainly no performance improvement running the reactor with distilled water.
Figure 1. Effluent pH vs time in hours. Comparison of performance between tap water and distilled water.
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