Continnally from the last paper¹⁾ , the effect of dynamic moisture content in air on the aeration of β-CaSO₄·III, and the behavior of moisture movement between CaSO₄·2 H₂O and β-CaSO₄ ·III in the closed vessel were studied. And discussed on the each stage of aeration by the DTA curve and the adsorption isotherm of watervapour.

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Packing characteristics of the bed of granular limestone are closely correlated with the performance of lime shaft kilns in relation to the flow phenomena of gases through the bed. Because of the difficulties and the general uncertainty of the state of knowledge on the packing characteristcs, the equations and the experimental data obtained on the subject by many different workers are by no means of general application.
In this paper, the packing characteristics of the bed of commercially crushed granular limestones ranging from 5.31 (mm) to 113 (mm) in size were delt with from a standpoint of design and operation of the lime shaft kiln.
The results obtained may be summerized as follows : (1) Mean fractional pore volumes were considerably affected by the ratio D_p/D_t in the whole range of it in the unconsolidated, multi-component particle mixtures of irregular-shaped limestone crushed in commercial plants. This finding was in contrast to the fact that the voidages in the bed of uniform glass sphere were unaffected by that ratio within the limits of (D_p/D_t) ≤0. 1. (2) Voidage free from wall effect kept a constant value of 0.47 (%) which was unaffected by any values of D_p and of the ratio D_p/D_t. (3) Voidages adjacent to kiln wall were considerably influenced by the ratio, and the values of the ratio ε_w/ε_c, ranged from 1.3 to 1.28 according to the ratio D_p/D_t=0.1 and Dp/Dt=0.05, respectively. (4) A shape factor φ, a correction factor, had an immediate connection with the method of particle-size measurement and was independent upon D_p and upon the ratio D_p/D_t, showing φ=1 for sieving screen method and φ=0.5 for vernier caliper method, respectively. (5) A fator α showing wall effect, adopted for practical convenience' sake, was differently correlated with the ratio D_p/D_t for different method of size measurement. (6) Numbers of particle packed in unit volume of the kiln being proportional with a slight gradient to the ratio D_p/D_t, mean values of the numbers of particle packed were reasonably related by a smooth curve with the mean particle diameters. (7) Effects of tapping or shaking the packed bed of irregular-shaped multi-component limestone particle mixtures upon voidage were fundamentally almost the same as these concerning uniform sphere particles oftained by different workers.

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