1982 年 98 巻 1135 号 p. 953-956
In order to disperse the clayey fine particles obtained from the disintegrated weathered granite in dry system, the authorsh ave performed sieving tests, observations of particle surface and measurements of powder characteristics, using the samplesb efore and after addition of metallic stearate. The results obtained are summarized as follows:
(1) From the degree of dispersion of sample, the optimum mixing time of the clayey sample with stearate was proved to be 5 minutes in the case of sample weight 70g in 800ml vessel a batch and mixing speed 14000r. p.m.
(2) Th e sieving of clayey sample through fine mesh in dry system were promoted notably by adding the metalic stearate. E specially, the most effective rates of addition were 3% of Mg-stearate and 5% of Na-stearate.
(3) Through the SEM observation, it was recognized that the many very fine particles agglomerating onto the surface of rather coarse particles were dispersed and removed by addition of the stearate, replacing partially those fine particles.
(4) Th e effect of addition of metallic stearate on the dispersion of the sample seems to be related to the adhesive forces among the particles. And the positive effect of stearate on promotion of sieving were proved also by the variation of dynamic properties, i. e. compactability or floodability index of the sample.