To investigate the maximum crushing strength of green pellets, the evaporization tendency of water contained in the pellets was examined.
The resulte obtained are as follows.
1. The crushing strength of green pellet is presumed by the measurement of drying rate of water from the pellets.
2. The crushing strength of green pellets depends not only on the size distribution patten of fine particles but also on the surface structure of the particles.
3. Fine particles with rough surface are effective to produce strong green pellets.

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A series of compression tests have been carried out with silica sands put in a square box (300mm×300mm×270mm) compressed with a punch the width of which is variable in 5 kinds of dimensions (293, 290, 260, 180 & 120mm). The distributions of the pressure and the friction stress on the inner surfaces of the box have been measured by using the pressure cells and the frictioncells developed by the authors. The following conclusions have been obtained.
(1) The pressure distribution below the punch is concave (low at the center) for small clearances between the punch and the sides of the box, and convex (high at the center) for large clearances. It has the minimum values at the places 30mm apart from the edges for intermediate clearances. It changes from concave to convex at about 40mm of clearances.
The friction stress distribution below the punch acts in the direction of pushing sands to the sides for small clearances, and keeping them in for large clearances.
(2) The stress distribution on the side is approximately uniform for small clearances, and the area with low stress occurs at the upper part and spreads with increase of dimension of clearances.
(3) The pressure distribution on the bottom is convex. The place where the maximum friction stress occurs approaches to the center with increase of dimension of clearances.
(4) The hysteresis effect in unloading is especially remarkable for smaller clearances.
(5) The ratios of the maximum pressures below the punch, on the bottom and the side to the mean pressure below the punch take the values in the ranges of 1.16-1.66, 0.76-1.19 and 0.275-0.527, respectively. The maximum friction stresses on those surfaces take the values in the ranges of 0.13-0.42, 0.12-0.30 and 0.04-0.32, respectively, in the ratios to the mean pressure below the punch.

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Spout region in fluidized beds similar to that in spouted beds is important for reaction, mass transfer and so on.
In the present paper, the spout diameter D_s and the spout height H_m above the distributor were tested in the semicylindrical fluidized bed by changing some factors, such as the geometry of perforated plates, particle size and operating conditions.
At first, an empirical correlation for H_m based on q_in has been obtained in the range of U/U_mf=1-7.
Next, the spout formed at each hole in perforated plate is assumed to be similar to that in spouted beds.
According to the assumption, a new empirical correlation for D_s and H_m in the fluidized bed has been presented by modifying the semi-empirical correlation in spouted beds.
It was found that D_s and H_m increased with increase of the superficial gas velocity for U/U_mf≤5, on the other hand, they were independent of the superficial gas velocity for U/U_mf>5.

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