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The first experimental task was to check the feasibility of a fluidized lime bed suspended in a tall column. This is the simplest model that can be used as a lime feeder. The aim was to find the optimum upflow velocity that would mix the lime uniformly and keep it suspended without causing a great amount of lime to go out with the effluent. Upflow velocity can be calculated by dividing the flow rate by the cross sectional area of the column. Since the area is constant, upflow velocity is directly proportional to the flow rate. The equation of up flow velocity is shown below.
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Vup flow: Velocity of the inlet flow.
As top: Superficial area at the top of the tube.
Qlime feeder: Flow rate employed on the experiment.
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The experimental set up can be seen in Figure 1. It consists in a vertical column that is fed by the bottom with water; the water flow rate is controlled by an automatic pump. Lime is added at the top of the column before running it. Once it is running, the effluent comes by the top; it is water hyper saturated with lime.
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Figure 1: Schematic Diagram of Experimental Set up
The Figure 2 shows the actual apparatus used for the first trial. A glass column connected with a water source regulated by a peristaltic pump.
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Figure 2: Experimental Apparatus
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