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The same experimental set up is used for the experiments run with the plate settlers, with a slight addition to the apparatus. A tube is in the top of the sedimentation tank with a pump to pull water off the top. The water then goes through the foam where a pressure sensor attached to both sides of the foam measures the pressure difference. This is used to calculated the head loss through the foam. The water then flows to a turbidimeter to see if the foam filtered out any floc particles that made their way into the effluent.
Figure 1: Schematic of experimental apparatus
All of the calculations performed for this experiment were done in MathCAD.
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The filter foam apparatus was first tested using the ramp state function used in the velocity gradient experiments. 
Figure 2: Head loss through the foam as a function of time
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