粒度に関するトロンプ配分率曲線の図式解法とボイドの補正について

抄録

Recently the Tromp's partition curve has been applied to evaluate the classification performance in the form of a classification diagram (size-partition curve). Its basal principle is the same as the partition curve for gravity separation. In handling practically the classification diagram, however, it is insufficient to construct it with the conventional methods used for the gravity separation, because of some particular difficulties such as, for instance, the inaccuracy of testing sieves and sizing work.
The authors had observed empirically the above fact, and contrived a graphical. method to construct the partition curve. This method is based on the properties of the cumulative weight curve. From the tangents of the cumulative weight curves of feed and two products (underflow and overflow), three weight-distribution curves are obtained, from which the partition curve is derived graphically. To get partition curve with the correction of void-filling material, the equation Z_o=Z_o(1-ω) is used, in which Z_o and Z_o are the distribution factor to overflow before and after the void correction respectively and w is the distrtbution percentage of water to un derflow.
The partition curves obtained with this method are practically accurate except at their both ends. This method can naturally be used for the gravity separation as well, and is expected to be useful to reduce the number of the gravity fractions in sink-float analysis.