# Doehlert Design for Wet Pelletization

Doehlert Design for Wet Pelletization

Consider the experimental design problem in which there are three factors: (1) impeller speed (in rpm) with associated variable , such that the lower and upper levels are 250 and 400, respectively, (2) amount of binding solution (in %) with associated variable , such that the lower and upper levels are 60 and 70, respectively, (3) pelletization time (in min) with associated variable , such that the lower and upper levels are 5 and 20, respectively.

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Pelletization experiments using Doehlert design scheme determine one parameter: the mean pellet size (in mm).

This Demonstration computes the quadratic model by multilinear regression; the response versus , , and is given by:

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y=1594-97.5+117.6+16.7-20.0-379.0-70.8-223.4+120.1+83.0

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You can set the value of one of the variables (say ) and the Demonstration will display the contour plot of the response versus the other two variables (and ).

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