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Then, head loss through both the tubing and orifice plates are calculated given user input for width and number of orifice plates along with the length of the desired tubing. This total head loss through the system is the summation of the head loss through the orifices plates and the head loss through the wider, encompassing tubing.
Head Loss Through Orifice Plates:
Head Loss Through Tubing:
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Using this information, the necessary flow of alum from the doser based on dimensions given above is determined. Using a stock dose concentration of 1.5 mg/L, the necessary stock concentration is found as well.
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The following section calculates the flow of alum given varying alum stock heights (of 5 inches to 25 inches). The final graph depicts results showing that if alum stock height varies greatly, the flow remains generally within the acceptable flow error. This error stems from the fact that we are not using alum for flocculation.
These results prove that the design will not work well with our point-of-use unit. By playing with the dimensions of the tubing, orifice plates, alum doser itself, and more, the lowest average flow we could obtain was around 12 mL/s which is extremely high for our desired system. Given this value, 1,037 L of alum stock would be used per day.